RESUMO
BACKGROUND: Primary mediastinal seminoma is a rare neoplasm. Cisplatin-based chemotherapy is the standard treatment, but management of post-chemotherapy seminoma residuals is still controversial. We encountered four cases of primary mediastinal seminoma and reviewed the clinical characteristics and outcomes, focusing on tumor size and F-18 fluorodeoxyglucose positron emission tomography (FDG-PET) findings after chemotherapy. METHODS: A retrospective review was performed of four consecutive patients with primary mediastinal seminoma treated in our institution between 2006 and 2010. All patients were young adult males with a median age of 31.3 years (range: 20-46 years). All patients were treated with three to four cycles of a combination of cisplatin, bleomycin, and etoposide, and FDG-PET was performed after chemotherapy. RESULTS: The response to chemotherapy was good in all patients. After chemotherapy, the findings of the FDG-PET were negative in three subjects. Two of the patients, with tumors measuring over 30 mm, underwent surgical resection for the residual mass and revealed necrotic tissues and no viable cells. A third patient remained stable without salvage surgery. The size of the residual mass in the remaining patient was less than 30 mm, but the FDP-PET result was positive and the mass considered inoperable because of the involvement of large vessels. Subsequently, radiotherapy was added for the residual tumor, but disease progression was seen seven months after the initiation of chemotherapy. CONCLUSIONS: FDG-PET findings after chemotherapy could be useful as a tool for the prediction of viable residual tumor in post chemotherapy residual mediastinal seminoma.
